1. Field of the Invention
This invention relates to a miniaturized electronic component device such as pulse transformer, wide-band transformer, delay line circuit device or the like, which comprises a component body including at least one coil, and external terminals having the leads of said at least one coil connected thereto.
2. Description of the Prior Art
In order to have a better understanding of the present invention, description will first be made of conventional electronic component devices of this type with reference to FIGS. 1 to 4 of the accompanying drawings. FIG. 1 shows, in a plan view, an example of the conventional electronic component devices, with the encapsulation thereof being omitted. FIG. 2 is a sectional view taken along the lines II--II of FIG. 1.
The conventional electronic component device shown in FIGS. 1 and 2 comprises a component body including at least one coil, though not shown. The component body is entirely embedded in a protecting elastic body 1 which is formed of silicone rubber or the like. The leads 2 of the coil are led out through the protecting elastic body 1. The component body entirely embedded in the protecting elastic body 1 is accommodated in an insulating case 3 which is opened at the top face thereof. External terminals 4 are attached to the opposite side walls of the insulating case 3, and have their upper ends project out of the top margin of the insulating case 3. The leads 2 of the coil are wound and soldered onto the upper ends of the external terminals 4 to be electrically connected thereto. The insulating case 3 is encapsulated with an insulating resin material as shown by an alternate long and short dash line 5 in such a manner that the free end portion of each of the external terminals 4 is exposed through the encapsulation.
FIG. 3 shows, in a plan view, another example of the conventional electronic component devices, which comprises two separate component bodies embedded in protecting elastic bodies as indicated at 1a and 1b respectively and accommodated in an insulating case 3.
FIG. 4 shows, in a sectional view, still another example of the conventional electronic component devices, wherein straight external terminals 6 are attached in such a manner as to extend through the bottom wall of an insulating case 3 which is opened at the top face thereof; leads 2 are wound and soldered onto the upper end portions of the external terminals 6; and encapsulation is provided covering only the top face of the insulating case 3 and the upper end portions of the external terminals 6, as shown by an alternate long and short dash line 7.
However, the above-mentioned conventional electronic component devices are disadvantageous in the following points:
Firstly, the packing volume is small for the reason that since the external terminals 4 or 6 are securely attached to the wall of the insulating case 3 accommodating the component body embedded in the protecting elastic body 1, the wall thickness of the insulating case 3 should be increased to enhance the strength of the insulating case 3 so that the insulating case 3 has only a limited accommodation capacity.
Secondly, automatic assembling is difficult to achieve for the reason that the connection of the leads 2 of the component body to the external terminals 4 or 6 is effected by winding the free end portions of the leads 2 onto the upper end portions of the external terminals 4 or 6.
Thirdly, in the case where the number of the leads 2 led out of the component body is large, the leads 2 are connected to the external terminals 4 or 6 while crossing each other. Thus, there is a possibility that the leads 2 may be shorted or cut off during the assembling operation. This makes it more difficult to achieve automatic assembling. Especially, in the case where plural component bodies are accommodated in the single case 3 as shown in FIG. 3, there is an increased possibility that the leads 2 may cross each other, so that the leads 2 are more liable to be shorted or cut off.